DEV: Rerun CreateTranslationIndexes migration (#251)

The previous version of the migration is not idempotent and can result
in indexes created but marked as "invalid" by Postgres.

Per postgres documentation:

If a problem arises while scanning the table, such as a deadlock or a
uniqueness violation in a unique index,
the CREATE INDEX command will fail but leave behind an "invalid" index.
This index will be ignored for querying
purposes because it might be incomplete; however it will still consume
update overhead. The recommended recovery
  method in such cases is to drop the index and try again to perform
  CREATE INDEX CONCURRENTLY.

Author: tgxworld

db/migrate/20250205082402_create_translation_indexes.rb

@@ -0,0 +1,33 @@
+# frozen_string_literal: true
+
+class CreateTranslationIndexes < ActiveRecord::Migration[7.2]
+  disable_ddl_transaction!
+
+  def up
+    remove_index :discourse_translator_topic_translations,
+                 %i[topic_id locale],
+                 unique: true,
+                 algorithm: :concurrently,
+                 if_exists: true
+
+    add_index :discourse_translator_topic_translations,
+              %i[topic_id locale],
+              unique: true,
+              algorithm: :concurrently
+
+    remove_index :discourse_translator_post_translations,
+                 %i[post_id locale],
+                 unique: true,
+                 algorithm: :concurrently,
+                 if_exists: true
+
+    add_index :discourse_translator_post_translations,
+              %i[post_id locale],
+              unique: true,
+              algorithm: :concurrently
+  end
+
+  def down
+    raise ActiveRecord::IrreversibleMigration
+  end
+end